Diagrammatic expansion for positive density-response spectra: Application to the electron gas

A. -M. Uimonen, G. Stefanucci, Y. Pavlyukh +1

In a recent paper [Phys. Rev. B 90, 115134 (2014)] we put forward a diagrammatic expansion for the self-energy which guarantees the positivity of the spectral function. In this wor…